Having too many persona can be problematic when you:

A. use different personae to deliberately deceive someone

B. change your persona according to your comfort level

C. gently adapt to a situation to achieve a desired outcome

D. allow your audience to dictate which persona to take on

I would say the correct answer is A. use different personae to deliberately deceive someone.

It is never a good thing to be such a person who uses other people and deceives them in order to gain something for themselves. However, if you change your personae based on your comfort level, to achieve a nice outcome, or to appeal to your audience, that is fine.